Method and apparatus for measuring temperature of ultra small areas

• US 4,613,238 A
• Filed: 09/27/1985
• Issued: 09/23/1986
• Est. Priority Date: 09/27/1985
• Status: Expired due to Fees

• Current Assignee: The Research Foundation for The State University of New York (State University of New York)
• Original Assignee: The Research Foundation for The State University of New York (State University of New York)
• Inventors: Sachs, Frederick
• Primary Examiner(s): Yasich, Daniel M.
• Application Number:
  US06/781,245
• Time in Patent Office: 361 Days
• Field of Search: 374/174, 374/185, 374/165
• US Class Current: 374/174
• CPC Class Codes: G01K 7/26 the element being an electrolyte
• CPC Class Codes: Y10S 204/06 Unusual non-204 uses of electrolysis

Abstract

The present invention provides a method and apparatus for measuring the temperature in an ultra small area by determining the electrical resistance, or changes in electrical resistance in an electrical circuit. The system utilizes a temperature sensory element comprised of a microcapillary tube containing an ionic liquid and an electrical circuit capable of measuring the electrical resistance, or the changes in the electrical resistance, of the liquid. The temperature sensory element is of a size useful to measure the temperature in ultra small areas. The temperature sensory element ranges up to about 2.0 microns in outside diameter, and more preferably has an outside diameter between about 0.1 and about 1.0 micron, and most preferably between about 0.5 and about 1.5 micron. Minute changes in the electrical resistance of the liquid within the temperature sensory element reflect minute temperature changes in the immediate area of the temperature sensory element.

Claims

1. A temperature measuring system for an ultra small area in which temperature is determined by electrical resistance, or by a change in electrical resistance, of an electrical circuit comprising:

(a) A temperature sensory element comprised of a thinwalled microcapillary tube having a sensing contact tip, said microcapillary tube having a septum and containing an ionic liquid having determinable electric resistance, said microcapillary tube having an outside diameter less than about 2.0 microns at the sensing tip.

(b) an electrical source,

(c) means to electrically connect said ionic liquid in said temperature sensory element to said electrical source to form an electrical circuit, and

(d) means to electrically connect said ionic liquid to an indicator to determine a change in the electrical resistance of said circuit caused by a change in the temperature of said ionic liquid as the sensing tip contacts the areas measured.

2. The system of claim 1 wherein said microcapillary tube has an outisde diameter between about 0.1 and about 1.0 microns.

3. The system of claim 1 wherein said microcapillary tube is fabricated of glass.

4. The system of claim 1 wherein said microcapillary tube is a micro U-tube.

5. The system of claim 1 wherein the said electrical source has a constant electrical potential.

6. The system of claim 1 wherein the electrical source is direct current.

7. The system of claim 1 wherein the electrical source is alternating current.

8. The system of claim 1 wherein the ionic liquid is an electrolyte.

9. The system of claim 1 wherein the ionic liquid is a mixture of a polar organic material and an electrolyte.

10. The system of claim 1 wherein the time of response to change of resistance is less than 1.0 millisecond.

11. A method of determining temperature of an ultra small area, in which the temperature is determined by electrical resistance, or by a change in electrical resistance, of an electrical circuit, comprising the steps of:

(a) contacting said ultra small area with a temperature sensory element comprised of a thin walled microcapillary tube having a septum and a sensing tip, said microcapillary tube containing an ionic liquid having a determinable electrical resistance, said microcapillary tube having an outside diameter less than about 2.0 microns at the sensing tip.

(b) electrically connecting said ionic liquid in said temperature sensory element with an electrical source to form an electrical circuit, and

(c) measuring any change in electrical resistance of said ionic liquid with said circuit caused by a change in temperature in said ionic liquid in said sensory element in contact with said ultra small area to determine the temperature of said ultra small area.

12. The method of claim 11 wherein said microcapillary tube has a diameter between about 0.1 and about 1.0 microns.

13. The method of claim 11 wherein the said electrical source has a constant potential and the resistance, or change in resistance, of the circuit is determined by change in potential.

14. The method of claim 11 wherein the electrical source is direct current.

15. The method of claim 11 wherein the electrical source is alternating current.

16. The method of claim 11 wherein the microcapillary tube is fabricated of glass.

17. The method of claim 11 wherein the microcapillary tube is a micro U-tube.

18. The method of claim 11 wherein the ionic liquid is an electrolyte.

19. The method of claim 11 wherein the ionic liquid is a mixture of a polar organic material and an electrolyte.

20. The method of claim 11 wherein the time of response to change in resistance is less than 1.0 millisecond.